Mortgage Loans Held For Investment And Related Assets (Schedule Of Portfolio Balance And Related Allowance) (Details) (USD $) In Thousands, unless otherwise specified	Oct. 31, 2012	Apr. 30, 2012
Accounts, Notes, Loans and Financing Receivable [Line Items]
Portfolio Balance	$ 385,867	$ 429,312
Related Allowance	18,125	26,540
Pooled [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Portfolio Balance	229,761	248,772
Related Allowance	6,892	9,237
Individually (TDRs) [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Portfolio Balance	63,602	71,949
Related Allowance	5,972	7,752
Individually [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Portfolio Balance	92,504	108,591
Related Allowance	$ 5,261	$ 9,551